The kinetics of self-diffusion of Ca2+ and Sr2+ ions into Linde molecular sieve A, and of Ca2+, Sr2+ and Ba2+ ions into Linde molecular sieve 13X, were studied using a radiochemical method. Energy barriers to self-diffusion were deduced from the Arrhenius equation (table 3). The entropies and free energies of activation were calculated. The migration of Ca2+, Sr2+, Ba2+ ions into several zeolite frameworks was considered, and its similarity to ionic migration in electrolytes was considered.

A Radiochemical Study of Cationic Self-Diffusion in Synthetic Zeolites. A.Dyer, J.M.Fawcett: Journal of Inorganic and Nuclear Chemistry, 1966, 28[2], 615-28

Table 3

Self-Diffusion Parameters for Synthetic Zeolites